linux-kernel - Re: [REGRESSION][BISECTED] Screen goes blank with ASpeed AST2300 in 6.18-rc2

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <798ba37a-41d0-4953-b8f5-8fe6c00f8dd3@googlemail.com>
Date: Wed, 22 Oct 2025 10:08:51 +0200
From: Peter Schneider <pschneider1968@...glemail.com>
To: Thomas Zimmermann <tzimmermann@...e.de>, regressions@...ts.linux.dev,
 LKML <linux-kernel@...r.kernel.org>
Cc: dri-devel@...ts.freedesktop.org, stable@...r.kernel.org,
 jfalempe@...hat.com, airlied@...hat.com, dianders@...omium.org,
 nbowler@...conx.ca, Linus Torvalds <torvalds@...ux-foundation.org>,
 Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
 Thorsten Leemhuis <regressions@...mhuis.info>
Subject: Re: [REGRESSION][BISECTED] Screen goes blank with ASpeed AST2300 in
 6.18-rc2

Hi Thomas,

thanks very much for your quick response!

(adding Thorsten to CC)


Am 22.10.2025 um 08:51 schrieb Thomas Zimmermann:
> Hi
> 
> Am 22.10.25 um 05:27 schrieb Peter Schneider:
>> #regzbot introduced: 6f719373b943a955fee6fc2012aed207b65e2854
>>
>> Hi all,
>>
>> I have encountered a serious (for me) regression with 6.18-rc2 on my 2-socket Ivy Bridge Xeon E5-2697 v2 server. After 
>> booting, my console screen goes blank and stays blank. 6.18-rc1 was still fine.
>>
>> The machine has an Asus Z9PE-D16 server mainboard with an onboard ASpeed AST2300 VGA chip with 16MB VRAM. I have 
>> attached an older HP Monitor to it via old VGA jack/cable. It also has a second graphics card in a PCI-E slot; an 
>> older NVidia GTX 560. It is not connected to a monitor, but I have configured it via kernel command line for PCI-pass- 
>> through to VMs running on this server (I use Proxmox VE, i.e. QEMU/KVM virtual machines). Currently, no VMs use this 
>> yet, and also no VMs are autostarting with machine boot. So when this regression occurs, the server is idle. Pressing 
>> a key on the keyboard does not make the screen come alive. The server is running fine though, and I can access it via 
>> SSH. It just has no graphic output anymore. In case this is important, the machine also has a ASMB6 BMC (can be used 
>> via http).
>>
>> I have attached dmesg output from both 6.18-rc1 which is fine, and 6.18-rc2 which exhibits this bug. I have bisected 
>> the issue, please see attached git bisect.log.
> 
> Thanks for the detailed bug report.
> 
> Attached is a patch that partially reverts the broken commit. Could you please apply it on top of the broken kernel and 
> report on the results?
> 
> Best regards
> Thomas


Your patch applied cleanly against 6.18-rc2 and the kernel built fine, but unfortunately it did not solve the issue: my 
console screen stays blank after booting. This is regardless whether I do a soft reboot, press the reset button or power 
cycle and do a cold boot. They are all the same.


Beste Grüße,
Peter Schneider

-- 
Climb the mountain not to plant your flag, but to embrace the challenge,
enjoy the air and behold the view. Climb it so you can see the world,
not so the world can see you.                    -- David McCullough Jr.

OpenPGP:  0xA3828BD796CCE11A8CADE8866E3A92C92C3FF244
Download: https://www.peters-netzplatz.de/download/pschneider1968_pub.asc
https://keys.mailvelope.com/pks/lookup?op=get&search=pschneider1968@googlemail.com
https://keys.mailvelope.com/pks/lookup?op=get&search=pschneider1968@gmail.com